1. Field
The invention relates to an image sensing panel and apparatus and, in particular, to an active matrix image sensing panel and apparatus.
2. Related Art
In the conventional X-ray imaging technology, images are produced by applying X-ray exposure to photographic film. In recent years, however, with the well development of semiconductor technology, X-ray imaging is improved to the so-called digital radiography (DR) technology that uses a flat and digital image sensing panel to produce images.
The principle of the digital radiography technology is briefly illustrated as below. When X-ray enters into an image sensing apparatus, a scintillator will convert X-ray into visible light that is then sensed by photosensors and thus converted into electric signals read out by data lines, and the images will be produced after processing the electric signals. As for the present DR technology, the photosensor is improved to silicon-based photodiode from charge coupled device (CCD), and also, X-ray is directly converted into electric signals without the scintillator.
FIG. 1 is a top-view diagram of a pixel layout of an image sensing panel applied to X-ray, showing one of the pixel structures. The pixel structure includes a data line 101, a scan line 102, a thin-film transistor (TFT) T, and a photosensor 104. The scan line 102 is electrically connected with the gate electrode 103 of the thin-film transistor T. The photosensor 104 is electrically connected with the drain 105 of the thin-film transistor T through a via V11. The data line 101 is electrically connected with the source 106 of the thin-film transistor T through a via V12. The photosensor 104 is also electrically connected with a bias line 107 through a via V13.
Entering into the photosensor 104, the light excites electron-hole pairs in the semiconductor layer of the photosensor 104. Meanwhile, a bias voltage is applied to the photosensor 104 through the bias line 107 so that the electron-hole pairs can be separated into electrons and holes as signals. The signals are transmitted to the drain of the TFT T through the via V11. Meanwhile, the scan line 102 enables the gate electrode 103 so that the signals can be read out by the data line 101 through the via V12. After the signals of all pixels are respectively read out, they can be processed by the processing module to produce the images.
However, during the manufacturing process of the image sensing panel, ambient particles often fall down to the pixel structure, causing the data line break. Besides, because the pixel structure is manufactured layer by layer, the broken portion of the data line is incapable of being repaired. Accordingly, the product yield is reduced.
Therefore, it is an important subject to provide an active matrix image sensing panel and apparatus that can eliminate the problem caused by the broken data line to improve the product yield.